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I would be interested in access to an IR camera as well. I would like to focus on insulation improvements myself.

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Richard Casto
1972 Porsche 914
2013 Honda Fit Sport
2015 Honda Fit EX
http://motorsport.zyyz.com
Money can't buy happiness, but somehow it's more comfortable to cry in a Porsche than a Kia.

I looked into this pretty seriously when we were planning for our house, which is now ~1.5 years old.

We obviously have plenty of land, and I have a backhoe which could have been used to dig the trenches for the loops to save some $$$, but I could not come anywhere close to justifying the cost. The best estimate I could come up with on a break even point was ~20 years, which made no sense.

Now, keep in mind that at the time, the gov't tax breaks and/or cost sharing were just in the planning stages, though with some of the estimates I came up with they wouldn't have even come close to making it workable.

I kept hearing that Geothermal systems were about 20-30% higher than other types of heating/AC systems, but what I found is that it would be 200-400% more. I think a part of the problem was that there were only 2-3 people who specialized in these systems in this area, I think there are more options now.


I think it's a GREAT idea, something that just makes good basic common sense- not some hocus-pocus idea that's impossible to understand how it works.

I know that when my current system dies- I'll be seriously looking into it again.

BTW- we ended up with an electric heat pump system, and I'll have to say we've been very pleased with it. Our highest bill this winter was about 2x what the "normal" bill would be during winter, but it was still only ~$250. Granted, we keep the thermostat set a bit lower than most folks would consider comfortable, but I'll wear an extra shirt or sweater if it means paying lower electric bills.


Natural gas is not an option where we live, so Propane or Fuel oil would be our only other options if we didn't go with a heat pump, and with the way fuel costs were skyrocketing back when we were planning this house, there was no way I was going with either of those.

Thanks for chiming in with your experiences Brett.

It's looking to be a good time to consider geothermal. There is a Federal 30% tax credit, and just last year NC introduced a 35% tax credit with a very high limit (like $8400). I will be getting a quote next week.

I expect to find that the system would be $15-20k or so installed, less Fed 30% and NC 35%, so probably $8k after considering other tax implications (Fed tax on NC credit). This would be to retrofit an existing split system -- gas pack down and split gas/AC up, reusing existing refrigerant lines in the walls.

Sounds like I could expect a 60+% reduction in heating bills and 50+% AC. Our consumption is pretty high (big house) so probably $2k potential savings per year, so less than a 5 year payback. Plus everything is in ground or in the crawlspace so the system life expectancy is 25+ years.

Will keep eveyone posted on what I learn. Time to make a big spreadsheet

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

That's just crazy. Your expected savings are about what I pay for my gas/electric annually.

It's no wonder that I always come up on the short end of the stick when I do my "high efficiency" payback calculations.

That said, with the incentives/rebates/tax credits, I am probably going to get some quotes on solar stuff this spring. Unfortunately, before I can put a bunch of expensive solar panels on my roof, I need it to be a roof that isn't already 20+ years old.

What Bret said about the lack of providers is from what I have heard true. A friend of mine had a contractor die in the middle of his job and since it was a small company that put somewhat of a monkey wrench in it. Luckily the guys working there finished it up and I think were trying to keep the company going, but this was several years ago

He has an old farm house and he said with his tax credit (3 years ago or so) and his energy savings, his payback was much shorter than the 20 years.

You're not on propane heat are you. That's the killer for us.

We're at about $2000-$2500k in propane per year (at $2-$2.70 a gallon) and seeing $80-100 a month in the summer for cooling. So call it $3000 a year in expenses. So realistically maybe $1500 a year in savings, possibly more if we go really high efficiency on geothermal (at like 80% now on the gaspacks).

Just switching to Nat Gas at $1 a therm would net about $1000-1500 in savings. Propane just plain sucks these days, and I don't see it getting any better. Propane has more than doubled in price since we moved here in 2002.

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

Try calling around for better prices. From some of what I've heard, different propane companies charge wildly varying rates for the stuff. It may not all be apples to apples, with contract terms, tank rentals, etc, but at least it would be some other data points. Maybe you could even take that info back to your current co and ask for a discount. For some reason, propane prices seem to be more flexible than other energy costs.

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Carl Fisher

Be Cool to the Pizza Dude:
http://www.npr.org/templates/story/stor ... Id=4651531

Well our last 2 fills were $2.55 per gallon. In the summer it was about $2.00. Anyone have anything better?

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

Update.

We are about to pull the trigger on a geothermal (ground source heat pump) install. I have gotten quotes from 3 companies. Here's how the numbers shake out:

$30k install cost:

$18k for the house-side install
- Climatemaster (owned by Carrier) Tranquility 27
- 3 ton split upstairs system, 2 ton single unit downstairs
- no duct work needed, all our existing stuff is good
- all systems in the crawlspace, nothing outside
- dual stage compressor and fan sized to be basically running all the time on first stage (good for air filtering, quiet op, and consistent temps)
- includes "desuperheater" which provides 95F inlet water TO our propane water heater

$12k for 3-4 vertical closed loop wells, about 800 lin ft well depth
- includes all the tubes installed
- includes the thermal grout which is pumped into the hole
- 50 year warranty (or just life expectancy?)

Discounts:
- $9k Fed back next year
- $8400 State over 2 years
- $600 from Progress Energy
- Total out of pocket about $14k

Expected savings
- heat, cool, and hwh expenses in our house is about $4200 per year
- conservative estimate (my own) is about $2000
- liberal estimate (theirs) is about $1500
- This is about 75% reduction in heat cost, 50% cooling, and 50% hot water
- At conservative estimates and constant energy prices it's about 6 year payback
- At liberal estimates and continued propane increases it's about a 4 year payback

Intangibles
- get open flames out of the attic
- existing gaspack 7 years old and according the the hvac dude today I shouldn't expect much more from this model, so a pending $5k replacement coming anyways
- good to go green
- 30 year life expectancy on units. In crawlspace, not exposed to elements, not working "hard" with a 61F water source temp year round

Risks
- I'm not considering lost opportunity cost, but considering that it's a 30 year continued return I'm sure it still looks favorable to "traditional" investments
- Puts us at risk for electricity price volatility. In my mind this is an issue if there are future government mandates for electric vehicle use. We live near a nuke plant, which makes me feel a bit better about that.
- This assumes we'll be in the house for a long time, which I plan to do. I'm sure we would not get our investment back if we sold the house.

This still feels crazy to do, but it looks less crazy the more people I talk to and the more I run the numbers. At our expected $14k out of pocket expense, it's comparable to doing a non-green replacement system of a different type, and is still much more cost effective than any solar or wind options I have looked into.

I'll let y'all know how it goes. We plan to pull the trigger by the end of next week. I have talked to about 10 HVAC companies and 6 drillers. Sounds like the systems are getting a lot more popular, and Climatemaster service and support sounds like it's the best out there with local distribution here in Raleigh.

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

Hard to argue with that math. Congrats.

Have they estimated how much water will be required from the wells to support the heat exchanger? That seems to be the only unknown and (I guess) the driver behind the 3-4 estimate? Unfortunately it seems hard to predict how much water wells will provide until you drill.

Any thought to adding a propane fueled generator as electrical backup?


Frank

Hi Mike,

Great analysis!!!

At $14K out of pocket after tax discounts, etc you probably are in the range of two heat pumps sized for your house or even my smaller house. If so, the "payback" for me might only be the need to do it before the tax benefits expire by replacing relatively new Lennox heat pumps which are 4/5 years old with R410A)

Curiousity (at this point) questions:

Did "they" explain the engineering basis for the 50 year in ground warranty/life expectancy and for the 30 year equipment life expectancy?

This is a long time for many of the parts. Is there any high pressure refrigerant in the system at all or is it all relatively low pressure pumped water/heat transfer medium?

Will the well be 800' deep? Wow (I think since my water well is about 350 feet). Where will they drill the well (i.e. near the curb)? Does the price include restoring the yard, street, driveway, etc. to pristine condition?

Are you saying that operating costs (electricity for pumps and compressor, maintanance, etc.) will be between $1500 and $2000 per year including water heating with propane with the high temperature boost from the geothermal? Is this boost for cooling and heating seasons?

Are the Fed and State "discounts" actual real money (tax credits/rebates versus deductions.)? If credits/rebates what happens if tax liability is less than the discount? Do the Fed/State send a check or can it be spread over several filing years?

Is well depth, etc. reduced it the heat/cooling load is less than yours?

Does the hot water heater desuperheater apply to electric water heaters also?

Thanks,

Dick

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Dick Rasmussen

FS 50 2018 Mustang GT

Does the well actually need to be more than "damp" to facilitate heat transfer along with the thermal grout? The loop itself is closed and presumably has some sort of non corrosive "heat transfer medium". i.e. is this more of a coolant to rock heat exchanger?

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Dick Rasmussen

FS 50 2018 Mustang GT

Mike,

I went to the manufacturer's and the IRS sites and answered the following questions:

Fed Tax credit on Geothermal DOES roll over to future years . . . at least through 2016.

There is a refrigerant that is compressed.

Dick

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Dick Rasmussen

FS 50 2018 Mustang GT

Typically two different techniques here - a true water producing well with a return well to keep the ground water resupplied. Or a closed vertical loop used when the lot size doesn't support a horizontal install. I think the rule of thumb is around 4 GPM of water (or coolant in a closed system) per ton of HVAC capacity.

Frank

Just as a comparison, we just replaced our system with a 4 ton Carrier split system. No ductwork needed either. Compressor outside, airhandler in crawlspace. It was $6200 installed before rebates/tax credits etc - roughly $4500 after rebates/credits 16 SEER rating.

The $14K doesn't sound out of line given the drilling and higher cost of hte system